Validation Rules Help

This one I have been putting off for a while and finally getting around to trying to solve it.

Maybe I just do not know enough about international domain extensions but what I need is a domain to match the email.

 

So take me for example me@davemaharaj.com would match davemaharaj.com easy enough.

 

But getting into international domain some end in .com.au yet their email ends in .com so sure break the url  apart at the (.)

Now the problem kicks in. No subdomains are allowed as a requirement for validation so any domain with something.some.extension are not valid.

 

So I have been playing around with getting DNS MX records to make sure the domain is actually real but it seems almost impossible to determine if a domain is actually a sub-domain or if it is actually just a domain with an extended international domain.

 

And to make things just that much better just finding random foreign sites with international domain extension like the .com.au I see their contact email is the same as the domain minus the .au…it ends in .com whats up with that? Why would the domain be .com.au on the web yet email be .com? I tried just typing in the url minus the .au and it directs to the full extension. Like I said maybe I just do not know enough about how the extensions work.

 

Any and all insight would be great.

 

Thanks,

 

Dave